Manufacture of structural material.



APPLIGATION FILED FEB.13, 1911.

Patented June 20, 1911.

WITN ES$ES Atty CHARLES E. DUNCAN, OF SAULT STE. MARIE, ONTARIO, CANADA, AND JOSEPH FAWELL, F PITTSBURG, PENNSYLVANIA; SAID DUNCAN ASSIGNOR TO SAID FAWELL.

MANUFACTURE OF STRUCTURAL MATERIAL.

ooaoor.

Specification 01 Letters Patent.

. i Application filed February 13, 1911. Serial No. 608,458.

To all whom it may concern:

Be it known that we, CHARLES E. DUN- CAN, residing at S'ault Ste. Marie, Ontario, Canada, a citizen of the United States, and JosEPH FAWELL, residing at Pittsburg, in the county of Allegheny and State of Pennsylvania, citizen of the United States, have invented or discovered certain new and useful Improvements in Manufacture-ofStruc tural Material, of which improvements the following is a specification.

As is well known to those skilled in the art, the lower flange' of an I beam or other structural shape when arranged horizontally on separated supports, forms the most im portant element in sustaining the load and that such-portion of such flange-as is farthest from the neutral axis of the beam 6. e. the lowermost portion of said flange will be subjected to the greatest strain. Hence in the manufacture of the beams care should be taken that no flaws or defects should occur in that portion of the flange and that the metal should not be put under injurious strains. b

Two forms or. types of mills are nowugenerally 1ised in the manufacture of beams, etc. The first consists of two or three high rolls having grooves progressively varying in contour and dimensions. known to those skilled in the art the reducing or shaping surfaces formed by the walls of the grooves vary greatly-in peripheral speed, especially if the flanges to be formed are wide. By reason of the variation of portions of the reducing surfaces from the rate of movement of the article be- 1 tween the rolls, and the factlthat the walls of the grooves which shape the flanges, differ most greatly from the rate of movement of the article, the metal of the flanges is sub; jected to great strains and there is a tendency to form cracks in the surfaces of the flanges especially the outer surfaces due to grinding and tearing action, when the reducing surfacesslip along the gradually cooling and stiffening metal. In the other form or type of mill generally known as a universal mill, consisting of horizontal and vertical rolls, the rolls are adjustable to effect the required variation of dimensions of the pass, as the article is fed back and forth between the rolls. In this mill the operative surfaces of the horizontal rolls are so shaped as to impart to the article, when the Web has been As is well of the flanges, when the beam is so as internal support for the flanges, while the latter are being sha ed and brought'to size by the vertical ro ls, which are adjustedinwardly toward each other after each pass. In thus rolling the beam the largest periphery of the horizontal rolls will have the highest peripheral speed and the rate of movement of the article through the rolls will be approximately the same. But the peripheral speed of the sides of the collars is slower proportionall; to their dis-- tance from the axes of the r0 ls, and hence will tend to have a retarding efl'ec't on the metal adjacent thereto. The vertical rolls, which operate on the outer faces of the flanges, will have a peripheral speed approximately equal to that of the article between the rolls. It will be readily understood that as the met-a1 in contact with the sides of the collars must be dragged along by the conjointpull. of tops of the collars and the vertical rolls, there will be a constant tendency to tear the metal, producing cracks transverse of the direction of movement of the article. These cracks, if formed, are closed up and not visible, and even if not formedthe tearing action of the rolls will have a weakening effect. Thisweakening of the web does not seriously affect the beam but the weakening of the outer faces placed that one of the flanges will be in tension, is believed to be detrimental.

The invention described herein hasfor its object the production of a structural shape in such manner that the outer faces of the flanges will be substantially free from cracks or injurious strains. The invention is hereinafter'more fully described and claimed.

In the accompanying drawing our improved method is diagrainmatically illustrated as applied to the manufacture of I beams.

In the practice of our invention, the ingot is broken down in a blooming or universal Patented June 20', 1911. i

mill and partially shaped. During this operation, reduction is effected at all points without anyinjury to the metal as it is so hot and plastic as torreadilyyield and flow under the pressure of the rolls without any tendency to tear. As the reduction continues the portions .which go to form the flanges become thinner and cooler and. the metal less plastic, so that in subsequent reductions the-change of shape is due mainly to flow under pressureand to some extent indicated by the outer lines 1, and all'subsequent reductions should be within planes coinciding wlth the outer faces of the flanges 2. These-reductions may be effected in a two or three high mill havinggrooves or passes formed therein suitable for the progressive reduction of the blank, or in a universal mill in which only the upper horizontal roll will be shifted during reduction; and the vertical rolls havingbeen adjusted a distanceapart equal or s'ubstantiallyequal to the desired depth of the beam, the latter Will not be substantially changed. l/Vhile the desired reduction may as stated be footed in a universal or a two high mill, it is preferred to employ a universal mill of.

x thetypeshown and claimed in the application of Charles E. Duncan and Joseph F awell' filed liebruary l3th, 1911, Serial No. 608,459, in which-the blank is reduced in a series of-fixed .passes' each formed by two hori7'ontal. andjltwo vertical rolls. employing,,thisqnilllthe dimensions of the" -operative porti;on s 1of the horizontal rolls arefch'anged for .each pass as cindicatedby "dotted lines in the drawing. In addition to f'fchanges dimensions;there will be also such sl igl 1t. changes-in.;oontour as are rea When quired to properly shape the portions of the beam within the flanges. I

It will be observed that in each pass a reduction of the web portion and'also of the thickness and width of the flange portions.

of the blank, is effected but that the relative positions ofthe outer faces of'the flanges are not substantially changed. As no substantial reduction of depth is effected the outer, faces of the flanges will, in a two high mill, simplyslide' along the reducing faces of the rolls to an extent equal to the difference of speed of the article and the .roll

faces; and the same is true when a universal mill is employed but not to so great extent,

hence there will not be any tendency to so tear the metal as to produce cracks or strains.

We claim hereln as our lnVBntlOIIZ 1. The method herein described of manufacturing structural materialwhich consists in first reducing an ingot or billet in one direction to orapproximately to its final dimensionhnd partially reducing the ingot or billet in other directions and then reducing such partially reduced portions to final dimensions.

2-. The method herein described of manu facturing structural material which consists in forming a blank having a depth, equal or approximately equal to that desired in thefinished article and reducing such blank to the finished article .without mate'rially changing-the depth of the blank.

3. The method herein described ofmanu- 'facturing structural material which consists in first forming a blank by reducing an ingot or billet 1n all 'dlrectlons, reduction in one directlon belng to or approximately to a finished dimension, and finally finishing the article by reductions of the blank oetween planes coinciding with the previously finished surfaces.

In testimony whereof,. we have hereunto set our hands. 3 V

CHARLES E. DUNCAN. JOSEPH FAWELL.

Witnesses: O soA BRASHEAR,

H. .HAsLAM;

Copies e f-this natentimfay'be' obtained for 'five cents each, addressing the "Commissioner. offatents'.

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